Упрощенная HTML-версия
One of the most modem and advanced methods of genetic engineering to
produce new microbial strains is genetic copying (cloning). Already in the early
70 - s of the twentieth century, scientists in the laboratory began to receive,
clone, recombinant DNA molecules, cultivated in test tubes cells, tissues, plants
and animals, enormous progress in cloning full of animals made in recent years
(even the ability to produce offspring) from somatic (m. e. no pun intended)
cells. Great response from the world community received the work of Scottish
scientists from the University of Roslin, which failed because of breast cells
genetically pregnant sheep get an accurate copy. The cloned a sheep named
Dolly normally developed and produced the first one and then another three
normal lambs. Following this, a number of new messages playback genetic twin
cows, mice, goats, pigs, monkeys from the somatic cells of animals. In 2000 he
had information about the clonal reproduction of the offspring of primates by
dividing an embryo. American researchers have managed to obtain genetically
identical embryos of rhesus monkeys in the separation of the blastomeres of the
embryo at the stage of division. From the embryo was born quite normal monkey
Tetra - a genetic twin of the original conception Special. This type of cloning
provides a genetically identical offspring and as a result you can get twins,
triplets or more genetic twins and have the opportunity to repeat the complex
scientific experiments on absolutely genetically identical material, implanting
consistently embryo the same surrogate mother can study the effect of her
organism to the development of the fetus.
The developed methods of animal cloning is still far from perfect. In the
process of experimentation, there is a high mortality rate and a high percentage
of neonatal malformations (from 226 experiments conducted in the laboratory of
Ian Wilmut at the Roslin Institute, the best was only one - was born Dolly the
sheep). It is not clear to many cloning mechanisms, development of animal
somatic cells. But the success achieved so far, showed the theoretical possibility
of creating genetic copies even human from a single cell taken from a - a body.
Many scientists enthusiastically embraced the idea of human cloning. For
example, the "father" of the first child "test-tube" L. Edwards, said that the
method can be used for "spare" organs for transplanting them to the sick person.
An opinion poll in the United States, 2000 indicated that 7% of Americans are
willing to undergo cloning. However, many scholars and public figures
concerned about the potential danger (including moral), and oppose the cloning
of human beings. There is a biological problem. It is known that during cell
culturing in vials, obtaining somatic clones may arise various kinds of mutations
in the genome that are harmful to the organism. It was established that the
individual clonal aging quickly and there is oppression of the many vital
functions in a short time. Consequently, human cloning could lead to an increase
in the human population is genetically defective, in Vol. H. Of mentally ill
people, and raises a number of moral, ethical and legal problems associated with
the manipulation of the human embryo.
170